The article discusses the theoretical and practical problems related to the study of speech genres on the basis of the material of databases, and generally using the methods of corpus linguistics. In the foreground there is the problem of “key phrases”, or text markers of speech genres, which can be searched in the case. According to the authors, the key phrase of speech genre is its essential characteristic, which is present in speech genre competence of a native speaker and should be included in the relevant speech genre description as an additional parameter.